Core B. Standardized and Experimental Testing Core The purpose of the Program Project as a whole is to study hierarchical levels of neural processing and cognition in children with Specific Language Impairment (LI), Early Unilateral Focal Lesions (FL), High Functioning Autism (HFA), and Williams Syndrome (WS) in order to identify specific neural underpinnings of their cognitive deficits. The purpose of the Standardized and Experimental Testing Core (Core B) is to provide psychometric testing services for all subjects (clinical populations and control subjects) enrolled in the program project. The nature of the testing is twofold. One aspect is to perform a standardized screening of subjects to evaluate their appropriateness for inclusion in the study, and to collect basic psychometric/neuropsychological data on subjects, which will be useful for the characterization of the subject groups and for the interpretation of experimental measures. Standardized assessments include measures of IQ, receptive and expressive language, academic functioning, motor and attentional functioning, neurological status, and medical and family history. The second aspect of the testing to be done in Core B is to perform the theory-driven experimental behavioral testing detailed in the individual projects (Projects 2-4). Experimental behavioral tasks will be designed by the scientific projects in order to assess hierarchical levels of neural processing and cognition, including spatial attention and working memory (Project 2), social and affective components of communication (Project 3), and language and literacy (Project 4). Core B will provide a centralized resource for all behavioral testing. As such, general psychometric functions of the Core are to organize and supervise the administration, scoring, and data entry of all standardized and experimental behavioral measures; compile detailed testing protocols and procedures for all measures administered; train all psychometrists and the data entry lab assistant; schedule and track the behavioral testing of all subjects; monitor the reliability and validity of behavioral assessments; ensure timely, accurate, and reliable coding/scoring and database entry of test data; oversee overall quality control of data collection and database entry; and send results letters to parents. The Core organization allows us to maximize the efficiency of testing and ensure the smooth flow of information regarding children's testing between the Projects and Cores. It also serves to enhance the consistency, reliability, and validity of data collection across all subject populations and Projects.